Zvinhu Zvinodzvinyirira Mvura
Mufizikisi, kumanikidzwa kunotsanangurwa sesimba pachikamu chimwe nechimwe, uko kutungamira kwesimba kwakatarisana nenzvimbo yepamusoro. Pamasvomhu, kumanikidzwa kunoratidzwa ne equation P = F/A, apo P = kumanikidzwa, F = simba uye A = nzvimbo yepamusoro. Chikamu chesimba (F) ndiNewton (N), chikamu chenzvimbo chiri square metres (m 2 ). Sezvo kumanikidzwa kuri simba pachikamu chimwe nechimwe, chikamu chesimba iN/m 2. Rimwe zita reN/m 2 ndipascal (Pa). Pascal inoshandiswa sechikamu chesimba mukukudza Blaise Pascal.
Kana mvura yakamira, inoshandisa simba rakamira pamusoro pese painosangana nayo. Semuenzaniso, funga nezvemvura iri mugirazi; chikamu chimwe nechimwe chemvura chinoshandisa simba rakamira pamadziro egirazi. Nokudaro, chikamu chimwe nechimwe chemvura chinoshandisa simba rakamira panzvimbo yega yega yemudziyo wainogara. Ichi chinhu chakakosha chemvura isingachinji, mvura yakamira. Kana mvura ikashandisa simba pamusoro, apo simba risiri rakamira, pamusoro payo pachava nesimba rekuita, kwete rakamira. Izvi zvichaita kuti mvura iyerere. Zvisinei, muchokwadi, mvura inoramba yakamira. Naizvozvo, mumvura yakamira, simba rinogara rakamira pamusoro pemudziyo wainogara.
Chimwe chinhu chakakosha chemvura iri payakamira ndechekuti inogara ichimanikidza kumativi ese. Kuti unzwisise izvi zviri nani, isa chinhu chinoyangarara mumudziyo wemvura. Kana mvura yakanyarara zvachose, chinhu chicharamba chakamira nekuti kumanikidzwa kuri pamusoro payo yese kwakaenzana. Kana kumanikidzwa kwemvura kusina kuenzana, pachava nesimba guru, iro richaita kuti chinhu chifambe.
Mhedzisiro yekudzika kwemvura pakumanikidzwa
Kudzika kana kukwirira kunokanganisa sei kumanikidzwa kwemvura? Kumanikidzwa kwemvura yegungwa pakadzika kwemamita gumi kwakafanana here nekumanikidzwa kwemvura yegungwa pakadzika kwemamita zana? Ngatifungei nezvekumanikidzwa kwemvura mumudziyo sezvakaratidzwa mumufananidzo. Kureba kwekoramu yemvura ndeye h uye nzvimbo yayo yepakati pechikamu iA. Chii chinonzi kumanikidzwa kwemvura pasi pemudziyo?
w = huremu hwemvura, h = kureba kwekoramu yemvura mumudziyo wakaita sedenderedzwa, A = nzvimbo yepamusoro uye P idzvinyiriro.
Information :
w = simba rinokwevera pasi
ρ = kuwanda
m = misa
g = kukurumidza nekuda kwesimba rinokwevera pasi
V = hA = vhoriyamu yekoramu yemvura (h = kureba, A = nzvimbo yepamusoro)
Kana tikaibatanidza mu pressure equation, tinowana:
p = ρ gh → Equation 1 (mudziyo wakavharwa)
p = pa + ρ gh → Equation 2 (mudziyo wakavhurika)
Information :
pa = Kumanikidzwa kwemhepo
ρ gh = Kumanikidzwa kwemvura
Mumufananidzo uri pamusoro, kumanikidzwa kwemhepo hakuratidzirwi, asi muchokwadi, kana mudziyo une mvura wakavhurika, kumanikidzwa kwemhepo kunoshandawo pamusoro pemvura, iyo inonangidzirwa pasi.
Zvichibva pamuenzaniso uri pamusoro apa, zvinoita sekunge kumanikidzwa kwakanangana nehuremu uye kudzika kwemvura (gravitational acceleration inoramba yakadaro). Sezvo kudzika kwemvura kuchiwedzera, kumanikidzwa kunowedzerawo. Mvura inenge isinganyanyi kumanikidzwa nekuda kwehuremu hwemvura iri pamusoro payo, saka huremu hwemvura hunoramba hwakafanana. Kana musiyano wekukwirira uri mukuru kwazvo (semuenzaniso, mumvura yakadzika kwazvo yegungwa), huremu hunosiyana zvishoma. Zvisinei, kana musiyano wekukwirira usina kukura zvakanyanya, huremu hwemvura hwakafanana kana kuti musiyano wacho mudiki zvekuti unogona kuregeredzwa.
Tinogona zvakare kushandisa equation iri pamusoro kuti tiverenge musiyano wekumanikidzwa pakadzika kwakasiyana. Equation iri pamusoro inogona kunyorwa patsva seizvi:
Kumanikidzwa kwemhepo
Patinonyura pasi pemvura, muviri wedu wese unoputirwa nemvura. Patinonyura zvakadzama, ndipo patinonzwa kumanikidzwa kukuru. Kutaura zvazviri, zuva rega rega tinenge takaputirwawo nemhepo, iyo inogara ichimanikidza zvikamu zvese zvemuviri wedu, sezvatinoita patinenge tiri pasi pemvura. Kungofanana nemvura yegungwa, pamusoro penyika panogona kufananidzwa ne "gungwa" remhepo. Kana chiri chokwadi kuti mhepo inodzvanyawo zvikamu zvese zvemuviri wedu nguva dzese, sei tisingazvinzwi, sekunge tiri pasi pegungwa? Masero emuviri wedu anochengetedza kumanikidzwa kwemukati kwakafanana nekumanikidzwa kwekunze. Ndokusaka tisinganzwi mhedzisiro yekusiyana uku kwekudzvanya.
Kumanikidzwa kwemhepo yepasi kunochinjawo nekukwirira. Zvisinei, kumanikidzwa kwemhepo kunosiyana zvishoma nekwemvura. Kuchinja kwehuwandu hwemvura kudiki zvikuru kana tichitarisa musiyano mudiki muhukuru, saka huwandu hwemvura hunofungidzirwa kuti hwakafanana. Izvi zvakasiyana nehukuru hwemhepo yepasi. Kumanikidzwa kwemhepo yepasi kunosiyana zvakanyanya nekukwirira. Kumanikidzwa kwemhepo pakukwirira kwakasiyana kwakasiyana, saka hatigone kuverenga kumanikidzwa kwemhepo tichishandisa equation yakawanikwa pamusoro apa. Uyezve, hapana muganhu wemhepo wakajeka unogona kuyerwa kubva pakukwirira. Kumanikidzwa kwemhepo kunosiyanawo nemamiriro ekunze. Kuti tizive kumanikidzwa kwemhepo, tinotora zviyero.
Kuyerwa kweDzvinyiriro
Evangelista Torricelli (1608–1647), mudzidzi waGalileo, akagadzira nzira yekuyera kumanikidzwa kwemhepo muna 1643 achishandisa mercury barometer yake. Barometer yacho yaive nechubhu refu yegirazi yakazadzwa nemercury. Chubhu yegirazi yakazadzwa nemercury yakapindurwa mundiro yakazadzwawo nemercury.
Kana chubhu yegirazi ine mercury ikatenderedzwa pasi, mugumo wechubhu hauna kuzadzwa nemercury, inongove ne mercury vapor ine pressure diki zvekuti haifungidzirwi (p).2 = 0). Pamusoro pemercury iri muplate, pane kumanikidzwa kwemhepo kunonangidzirwa pasi (mhepo inodzvanya mercury iri muplate). Kumanikidzwa kwemhepo uku kunotsigira koramu yemercury iri mugirazi tube. Mumufananidzo, kumanikidzwa kwemhepo kunofananidzirwa ne po Hukuru hwekumanikidzwa kwemhepo kunogona kuverengerwa uchishandisa equation:
p o = ρ gh
Zvichibva pamhedzisiro yekuyera, avhareji yekumanikidzwa kwemhepo pagungwa i1,013 x 10 5 N/m 2. Hukuru hwekumanikidzwa kwemhepo pagungwa hunoshandiswa kutsanangura imwe unit yekumanikidzwa, kureva atm (mhepo). Saka 1 atm = 1,013 x 10 5 N/m 2 = 101,3 kPa (kPa = kilo pascal). Imwe unit yekumanikidzwa ibar (inowanzoshandiswa mu meteorology). 1 bar = 1,00 x 10 5 N/m 2 = 100 kPa.
Ko kukosha kwekumanikidzwa kwemhepo kuri pamusoro apa kunowanikwa sei?
Kuyera uku kunoshandisa musimboti wakaratidzwa naTorricelli pamusoro apa. Kureba kwekoramu yemercury inoshandiswa i76 cm (kumanikidzwa kwemhepo kunogona kungotsigira koramu yemercury yakakwira 76,0 cm chete), apo tembiricha yemercury inoshandiswa iri 0 chaiyo. oC uye hukuru hwekumhanya kwesimba rinokwevera pasi i9,8 m/s2. Kuwanda kwemercury mumamiriro ezvinhu aya i13,6 x 103 kg / m3Kumanikidzwa kwemhepo:
Chiyero chekumanikidza
Kune maturusi akawanda anoshandiswa kuyera kumanikidzwa, kusanganisira open tube manometer.
Mumuchina unoyera mvura uri muchubhu yakavhurika, uko chubhu yacho yakaita seU, chubhu yacho inenge yakazadzwa zvishoma nemvura (mercury kana mvura). Kumanikidzwa kwakayerwa kwakabatana nemusiyano uripo pakati pehurefu hwemvura inopinzwa muchubhu. Kumanikidzwa kunoverengwa uchishandisa equation:
Kazhinji, hachisi chigadzirwa che ρ gh chinoverengerwa asi kukwirira kwemvura (h) nekuti kumanikidzwa dzimwe nguva kunoratidzwa mumamirimita e mercury (mm hg) kana mamirimita emvura (mm H 2 O). Rimwe zita re mm hg ndi torr (mukurangarira Evangelista Torricelli).
Kunze kwemanometer, kune zvimwewo zvishandiso zvekuyera, zvinoti aneroid barometers, zvese zvemakanika uye zvemagetsi, zvinosanganisira magauge epressure yematairi, nezvimwewo. Chishandiso chinoshandiswa naTorricelli kuyera pressure yemumhepo chinonziwo mercury barometer, uko chubhu yegirazi inozadzwa nemercury yozoshandurwa kuita ndiro ine mercury zvakare.
Kumanikidzwa Kwakayerwa, Kumanikidzwa kweGeji uye Kumanikidzwa Kwakakwana
Pakuzadza matai emotokari nemhepo, chiyereso chemhepo chinowanzo shandiswa. Izvi zvinoita kuti kumanikidzwa kwetairi kusanyanya kuderera kana kukwira zvakanyanya. Pakuzadza matai nemhepo, kumanikidzwa kwemhepo mukati metairi chete ndiko kunoyerwa. Kumanikidzwa kwemhepo hakufungidzirwi. Kwete chete pakuyera kumanikidzwa kwetairi, asiwo mune zvimwe zviyero zvakawanda zvekumanikidzwa, kumanikidzwa kwemhepo hakuyerwi. Kumanikidzwa uku kwakayerwa kunonzi kumanikidzwa kwakayerwa. Saka, musiyano uripi pakati peizvi nekumanikidzwa kwakakwana?
Kumanikidzwa kwakazara = kumanikidzwa kwemhepo + kumanikidzwa kwakayerwa. Saka kuti tiwane kumanikidzwa kwakazara, tinowedzera kumanikidzwa kwakayerwa kumanikidzwa kwemhepo. Nemamwe mashoko, kumanikidzwa kwakazara = kumanikidzwa kwakazara. Pamasvomhu, izvi zvinogona kunyorwa seizvi:
p = pa + p chiyero
Semuenzaniso, kana kumanikidzwa kwetai kwatinoyera = 100 kPa, saka kumanikidzwa kwakakwana ndekwekuti:
p = pa + p chiyero
p = 101 kPa + 100 kPa
p = 201 kPa
Kumanikidzwa kwakakwana = 201 kPa.
Kune rimwe izwi: gauge pressure, inozivikanwawo se gauge pressure. Gauge pressure idzvinyiriro yakawandisa pamusoro pe atmospheric pressure. Semuenzaniso, funga nezve tyre yemudhudhudhu. Kana tyre yemudhudhudhu yadzikira, dzvinyiriro iri mukati metyre yakaenzana ne atmospheric pressure (atmospheric pressure = 1,01 x 105 Pa = 101 kPa). Kana tyre yazara nemhepo, dzvinyiriro yetyre inowedzera zvega. Kana tyre pressure yadarika 101 kPa, dzvinyiriro yakawandisa inonziwo gauge pressure.
Muenzaniso weMibvunzo yeKumanikidzwa kweMvura
Muenzaniso wemubvunzo wechi1:
Ngarava yemugungwa inonyura kusvika pakadzika kwemamita mazana maviri. Simba remugungwa rinomanikidzwa zvakadini?
kunyura? g = 10 m/s2
Kukurukurirana
Zvinozivikanwa kuti:
Kudzika (h) = 200 m
Kuwanda kwemvura yegungwa (ρ) = 1,03 x 103 kg / m3 = 1030 kg / m3 (ona tafura yekuwanda kwevanhu)
Kumanikidzwa kwemhepo (pa) = 1 atm = 1 x 105 N / m2 = 1 x gumi5 (Kg m/s2)/m2 = 1 x gumi5 Kg/ms2
Kukurumidza kunokonzerwa negiravhiti (g) = 10 m/s2
Akabvunzwa: Kumanikidzwa
Mhinduro:
Mudziyo wacho wakavhurika saka kumanikidzwa kwemhepo hakusanganisirwi mukuverenga.
Muenzaniso wemubvunzo wechi2:
Dziva remvura rakareba mamita gumi rinozadzwa nemvura. Kana pamusoro pedziva remvura
yakavharwa, simba remvura riri pasi pechirongo nderei? g = 10 m/s2
Kukurukurirana
Zvinozivikanwa kuti:
Kureba (h) = 10 m
Kuwanda kwemvura (ρ) = 1,00 x 103 kg / m3 = 1000 kg / m3
Kumanikidzwa kwemhepo (pa) = 1 atm = 1 x 105 N / m2 = 1 x gumi5 (kg m/s2) / m2 = 1 x gumi5 Kg/ms2
Kukurumidza kunokonzerwa negiravhiti (g) = 10 m/s2
Akabvunzwa: Kumanikidzwa
Mhinduro:
Mudziyo wacho wakavharwa saka kumanikidzwa kwemhepo hakusanganiswi mukuverenga.
Muenzaniso wemubvunzo wechi3:
Kureba kwekoramu yemvura (kurudyi) = 50 cm, ukuwo kukwirira kwekoramu yemvura (kuruboshwe) = 30 cm. Kuwanda kwekoramu yemvura imwe chii?
Kukurukurirana
Zvinozivikanwa kuti:
Kukurumidza kunokonzerwa negiravhiti (g) = 10 m/s2
Chikamu chemvura (h)1) = 50 cm
Kuwanda kwemvura (ρ)1) = 1,00 x 103 kg / m3 = 1000 kg / m3
Kureba kwemamwe mvura (h)2) = 30 cm
Kuwanda kwezvimwe zvinwiwa (ρ)2) =?
pa + ρ 1 gh 1 = pa + ρ 2 gh 2
Kumanikidzwa kwemhepo (Pa) uye kukurumidza kwegiravhiti (g) zvakafanana, saka zvinodzima.
Muenzaniso wemubvunzo wechi4:
Mukati mechubhu yegirazi mune mvura ine urefu hwe 10 cm. Kumanikidzwa kwemvura pasi pechubhu iyi i 1200 N/m2Kana g = 10 m/s2Usafuratira kumanikidzwa kwemhepo. Huremu hwemvura hwakaita sei?
A. 800 kg/m3
B. 900 kg/m3
C. 1000 kg/m23
D. 1200 kg/m23
E. 1300 kg/m3
Kukurukurirana:
Zvinozivikanwa :
Ketinggian mvura (h) = 10 cm = 0,1 mamita
Kumanikidzwa kwemvura (P) pasi pechubhu = 1200 N/m2
Kukurumidza kweGravity (g) = 10 m/s2
Akabvunzwa :
Kuwanda kwevanhu mvura?
Jawab :
Kuwanda kwevanhu mvura yacho inosvika 1200 kg/m23.
Mhinduro chaiyo ndiD.
Muenzaniso wemubvunzo wechi5:
Mercury iri mumidziyo yakabatana ine musiyano wepamusoro we3 cm. Kuwanda kwemercury = 13,6 gr/cm3Kureba kwemvura iri muchubhu kuruboshwe i10 cm. Kuwanda kwemvura iyi kwakadii?
A. 800 kg/m3
B. 1030 kg/m3
C. 1080 kg/m23
D. 1300 kg/m23
E. 1360 kg/m3
Kukurukurirana:
Zvinozivikanwa :
Kureba (h) kweMercury = 3 cm = 0,03 m
Kuwanda kwemercury = 13,6 gr/cm3 = 13600 kg / m3
Kureba (h) kwemvura = 10 cm = 0,1 m
Akabvunzwa :
Kuwanda kwevanhu mvura?
Mhinduro:
Sistem berada dalam keadaan setimbang statis karenanya tekanan zat cair (tabung kiri) = tekanan raksa (tabung kanan)
Pmhepo +Pmvura =Pmhepo +Pzebaki
Kumanikidzwa kwemhepo kwakafanana saka kunobviswa kubva mu equation
P mvura = P mhepo
Mhinduro chaiyo ndiC.
